利用變溫及變壓吸附捕獲電廠煙道氣中二氧化碳之模擬

None

黃致翔(Chih-hsiang Huang)

指導教授 ： 周正堂 ； 楊閎舜

國立中央大學/工學院/化學工程與材料工程學系/碩士(2012年)

摘要

本研究以透過變溫及變壓吸附分離程序處理發電後所產生之煙道氣作為吸附設備模擬的對象(15.03% CO2和84.97% N2)，所使用的吸附劑為依台電綜合研究所配方製備的聚苯胺固態CO2吸附劑，目的為將二氧化碳濃縮(>90%)回收，以利之後儲存並減少二氧化碳排放至大氣中，減少溫室氣體的排放。
模擬程式中使用了method of lines結合upwind differences和cubic spline approximation，再以ODEPACK套裝軟體中之LSODE程式對時間作積分，估計出下段時間的濃度、溫度及壓力，之後一直重複循環計算到系統達到週期性穩態為止。
本研究使用了四種不同的吸附分離程序，分別為單塔五步驟變溫吸附程序、單塔兩步驟變壓吸附程序、單塔三步驟變壓吸附程序和雙塔六步驟變壓吸附程序。最佳的操作條件是由經過不同的操作變因探討後得到的，例如：吸脫附溫度、進料壓力、塔長及步驟時間等。
經過變因探討後得到的最佳程序為單塔三步驟變壓吸附程序，最佳操作條件為進料壓力6.0 atm、同向減壓壓力1.0 atm、逆向減壓壓力0.1 atm、塔長 98.3 cm、進料時間1200 s、同向減壓時間10 s及逆向減壓時間500 s。在此條件下其結果為二氧化碳濃度97.13%，回收率87.26%。捕捉每噸二氧化碳所需能耗為1.39 GJ/tonCO2。

關鍵字

變溫吸附 ； 二氧化碳 ； 煙道氣 ； 變壓吸附

並列摘要

In this simulation study, several adsorption process is utilized to separate CO2 and N2 from the power plant flue gas(15.03% CO2和84.97% N2) with solid polyaniline sorbent. CO2 can be recovered and sequestrated to reduce green- house-gas effects.
The method of lines is utilized, combined with upwind differences, cubic spline approximation and LSODE of ODEPACK software to solve the problem. The concentration, temperature, and adsorption quantity in the bed are integrated with respect to time by LSODE of ODEPACK software. The simulation is stopped when the system reaches a cyclic steady state.
Four different processes have been used in this study, single-bed five-step temperature swing adsorption (TSA) process, single-bed two-step pressure swing adsorption (PSA) process, single-bed three-step PSA process and dual-bed six-step PSA process. The optimal operating condition is obtained by varying the operating variables, such as adsorption temperature, desorption temperature, feed pressure, bed length, step time, etc.
After the variables discussion, the best process is single-bed three-step PSA process and the best operating condition is feed pressure 6.0 atm, cocurrent depressurization pressure 1.0 atm, vacuum pressure 0.1 atm, bed length 98.3 cm and step time at 1200, 10 and 500 s. The results of the best operating condition are 97.13% purity and 87.26% recovery of CO2 with an energy consumption of 1.39 GJ/tonCO2.

並列關鍵字

None

參考文獻

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[2] P. Guerin de Montgareuil and D. Domine, U.S. Patent 3,155,468 (1964), to Societe L’air Liquide, Paris.

[4] N.H. Berlin, U.S. Patent 3,280,536 (1966), to Esso Research and Engineering Company.

[5] G. Heinze, Belgian Patent 613,267 (1962), to Farbenfabriken Bayer A. G.

[6] D.E. Kowler and R.H. Kadlec, “The Optimal Control of a Periodic Adsorber: Part I. Experiment”, AIChE J., Vol. 18, pp. 1207-1212, 1972.